Using SNIF-NMR method to identify the adulteration of molasses spirit vinegar by synthetic acetic acid in rice vinegar.

摘要

Vinegar is one of the most commonly used sauces in Asia. However, cheap synthetic acetic acid or molasses spirit vinegar is widely used to adulterate pure fermented products. The aim of this study was to identify and evaluate pure rice vinegar by three model of rice vinegar authentication test. According to the analysis of SNIF-NMR method, the (D/H)_CH3 values for rice vinegar, molasses spirit vinegar, and synthetic vinegar are 98.50, 108.46 and 131.58 ppm. The results of (D/H)_CH3 showed that there are significant differences for different materials (p<0.05). In the rice vinegar authentication model test, the results showed that (D/H)_CH3 increases with the addition of molasses spirit vinegar or synthetic vinegar, and that there is a good linear correlation (R2 >0.97). According to these results, we consider the SNIF-NMR method to be an effective way of determining the degree of adulteration in fermented rice vinegar.